I agree their needs to be a easier way to stop it from playing
on mine to stop it if it has timed out (which it dose sometimes) or if I had had another app open while it's playing, i have to
hit the power button on the top
slide the unlock
slide up the widget screen to display all the widgets
scroll down to the music player widget
hit the music player widget
hit the song that's playing to bring up music player
hit the pause button.
that's a lot of steps just to stop it from playing a song.
You could just slide up your Apps screen and tap Music.